Things that must be done:

Curves, nice bezier splines.
Add support for other graphic primitives.
	- Polygons?
	- Bitmapped data (a lot faster to parse and plot)
	- Support for different thickness lines
	- etc.
Increase the speed of drawing.
Write some filters to turn jpg/gif/etc. into raw data.
Write some perl/awk/shell scripts to generate pretty patterns (mandelbrot in
awk?)
Work out what other uses this thing could have
Add a text tool
Add a cut and paste tool
Add an undo tool? This would require a double buffer or caching of data?
Work out how to do the drag animations smoothly (vsync?)
Create a front end whiteboard app to handle incoming/outgoing connections,
and dup fds for multiple users.
Stop using global variables and work out how to use userdata in widgets.
SPEED, everything is much too slow.
Add support for multiple input streams, could be easily done as soon as I
cba.
Extend the parser in logo.c to cope with recursive REPEAT calls.
Add functions (TO square REPEAT 4 [FD 50 LT 90] END) to logo.c
Fix the repeat statements in logo, they are very broken, - fails, nesting fails.

Things that mustn't be done:

Add network support
Output data in a non-readable form
Stop using stdin/stdout
